Bone Marrow Cells ; cytology ; Fibroblasts ; cytology ; metabolism ; Fibrosis ; Humans ; Myocardium ; pathology

Mitochondria are subcellular organelles that provide energy for the cell. They form a dynamic tubular network and play an important role in maintaining the cell function and integrity. Heart is a powerful organ that supplies the motivation for circulation, thereby requiring large amounts of energy. Thus, the healthiness of cardiomyocytes and mitochondria is necessary for the normal cardiac function. Mitochondria not only lie in the center of the cell apoptotic pathway, but also are the major source of reactive oxygen species (ROS) generation. Mitochondrial morphological change includes fission and fusion that are regulated by a large number of proteins. In this review we discuss the regulators of mitochondrial fission/fusion and their association with cell apoptosis, autophagy and ROS production in the heart.
Animals ; Apoptosis ; Heart ; Humans ; Mitochondria, Heart ; metabolism ; Myocardium ; cytology ; metabolism ; Reactive Oxygen Species ; metabolism

Objective To identify and verify the distribution of Telocytes derived from heterogeneous interstitial cells in the vital organs of ApoE mice.Methods Heart,kidney,and liver tissues were harvested from ApoE adult mice. Immunohistochemical assays were performed by using different immunobiological markers.Results Telocytes were found in these vital organs. The expressions of immunobiological markers differed among different organs. CD34,CD117,and CD28 were positively expressed in Telocytes in cardiac tissue;CD117 and plateled-derived growth factor-Α were negatively expressed in Telocytes in renal tissue;and CD117 and plateled-derived growth factor receptor-Α had negative expression in Telocytes in hepatic tissue. Furthermore,the distribution of Telocytes also differed in the same organ.Conclusions Telocytes exist in the vital organs of ApoE mice,as demonstrated by immunohistochemisty assay. The expressions of immunobiological markers differ among Telocytes in different organs.
Animals ; Antigens, CD34 ; metabolism ; CD28 Antigens ; metabolism ; Kidney ; cytology ; Liver ; cytology ; Mice ; Mice, Knockout, ApoE ; Myocardium ; cytology ; Proto-Oncogene Proteins c-kit ; metabolism ; Telocytes ; cytology

In developed countries, in which people have nutrient-rich diets, convenient environments, and access to numerous medications, the disease paradigm has changed. Nowadays, heart failure is one of the major causes of death. In spite of this, the therapeutic efficacies of medications are generally unsatisfactory. Although whole heart transplantation is ideal for younger patients with heart failure, many patients are deemed to be unsuitable for this type of surgery due to complications and/or age. The need for therapeutic alternatives to heart transplantation is great. Regenerative therapy is a strong option. For this purpose, several cell sources have been investigated, including intrinsic adult stem or progenitor cells and extrinsic pluripotent stem cells. Most intrinsic stem cells seem to contribute to a regenerative environment via paracrine factors and/or angiogenesis, whereas extrinsic pluripotent stem cells are unlimited sources of cardiomyocytes. In this review, we summarize the various strategies for using regenerative cardiomyocytes including our recent progressions: non-genetic approaches for the purification of cardiomyocytes and efficient transplantation. We expect that use of intrinsic and extrinsic stem cells in combination will enhance therapeutic effectiveness.
Animals ; Embryonic Stem Cells/cytology ; Humans ; Myocardium/*cytology/*metabolism ; Myocytes, Cardiac/*cytology ; *Regeneration ; Stem Cell Transplantation ; Tissue Engineering

We investigated the effect of phenylephrine (PE)- and isoproterenol (ISO)-induced cardiac hypertrophy on subcellular localization and expression of caveolin-3 and STAT3 in H9c2 cardiomyoblast cells. Caveolin-3 localization to plasma membrane was attenuated and localization of caveolin-3 to caveolae in the plasma membrane was 24.3% reduced by the catecholamine-induced hypertrophy. STAT3 and phospho-STAT3 were up-regulated but verapamil and cyclosporin A synergistically decreased the STAT3 and phospho-STAT3 levels in PE- and ISO-induced hypertrophic cells. Both expression and activation of STAT3 were increased in the nucleus by the hypertrophy. Immunofluorescence analysis revealed that the catecholamine-induced hypertrophy promoted nuclear localization of pY705-STAT3. Of interest, phosphorylation of pS727-STAT3 in mitochondria was significantly reduced by catecholamine-induced hypertrophy. In addition, mitochondrial complexes II and III were greatly down-regulated in the hypertrophic cells. Our data suggest that the alterations in nuclear and mitochondrial activation of STAT3 and caveolae localization of caveolin-3 are related to the development of the catecholamine-induced cardiac hypertrophy.
Animals ; Catecholamines/*pharmacology ; Caveolae/*metabolism ; Caveolin 3/*metabolism ; Cell Line ; Hypertrophy/metabolism ; Mitochondria/*metabolism ; Myocardium/cytology/*pathology ; Myocytes, Cardiac/cytology/*drug effects/metabolism ; Rats ; STAT3 Transcription Factor/*metabolism

AIMTo investigate the expression of androgen receptors in the extragenital tissues of developing human embryo.

METHODSUsing immunohistochemistry, we investigated the distribution of androgen receptor (AR) in the extragenital tissues of paraffin-embedded tissue sections of first trimester (8-12 weeks gestation) human embryos. Gender was determined by polymerized chain reaction.

RESULTSThere were no differences in the expression and distribution of AR in male and female embryos at any stage of gestation. AR expression was seen in the thymus gland. The bronchial epithelium of the lungs showed intense positive staining with surrounding stroma negative. Furthermore, positive staining for androgen receptor was exhibited in the spinal cord with a few positive cells in the surrounding tissues. Cardiac valves also showed strong positive staining but with faint reactivity of the surrounding cardiac muscle. There was no staining in kidney, adrenal, liver or bowel.

CONCLUSIONThis study demonstrates that immunoreactive AR protein is present in a wide variety of human first trimester fetal tissues and shows the potential for androgen affecting tissues, which are mostly not considered to be androgen dependent. Moreover, it implies that androgen might act as a trophic factor and affect the early development of these organs rather than simply sexual differentiation.

Bronchi ; cytology ; embryology ; metabolism ; Female ; Fetus ; cytology ; metabolism ; Heart ; embryology ; Humans ; Immunohistochemistry ; methods ; Male ; Myocardium ; cytology ; metabolism ; Pregnancy ; Pregnancy Trimester, First ; Receptors, Androgen ; genetics ; metabolism ; Spinal Cord ; cytology ; embryology ; metabolism ; Thymus Gland ; cytology ; embryology ; metabolism

OBJECTIVETo quantitatively detect the expression of connexins (Cx) mRNA in the posterior nodal extension (PNE) of adult rat heart and understand the relationship between Cx expression and atrial ventricular nodal reentrant tachycardia (AVNRT).

METHODSPNE was separated from adult rat heart by means of laser microdissection (LCM), and the cells were also isolated from the atrioventricular node (AVN), sinoatrial node (SAN), Purkinje fiber (PF), right atrium (RA) and right ventricle (RV), to serve as the controls. The Cx mRNA level was detected in these cells with quantitative real-time PCR (QRT-PCR).

RESULTSThe cells were successfully isolated from the PNE and other regions of adult rat heart, where heterogeneous expression of the 3 Cx isoforms (Cx43, Cx45, and Cx40) were observed. Cx45 mRNA showed higher expression in the PNE than in the working myocardium, whereas Cx43 mRNA level was about 25 times higher (P<0.05) in the working myocardium and 18 times higher (P<0.05) in the PF than in the PNE. In the PF, Cx40 mRNA level was proximately 6.8 times (P<0.01) as much as that in the PNE. Cx expression in the PNE was, however, similar to that in the SAN and AVN.

CONCLUSIONCx mRNAs exhibit heterogeneous expression in the PNE to allow the formation of the slow pathway. In addition, Cx expression in the PNE is very different from that in the adjacent myocardium, resulting in conduction discontinuity at the cellular junction, where, on certain occasion, unidirectional block may occur to cause AVNRT.

Animals ; Atrioventricular Node ; cytology ; metabolism ; Connexin 43 ; genetics ; Connexins ; genetics ; Female ; Male ; Myocardium ; cytology ; metabolism ; Purkinje Fibers ; cytology ; metabolism ; RNA, Messenger ; genetics ; metabolism ; Rats ; Rats, Sprague-Dawley ; Reverse Transcriptase Polymerase Chain Reaction ; Sinoatrial Node ; cytology ; metabolism

Animals ; Animals, Newborn ; Cells, Cultured ; Fibroblasts ; cytology ; metabolism ; Myocardium ; cytology ; Pravastatin ; pharmacology ; RNA, Messenger ; genetics ; metabolism ; Rats ; Rats, Sprague-Dawley ; Transforming Growth Factor beta1 ; genetics ; metabolism

OBJECTIVE[corrected] To assess the effects of metallothionein on myocyte apoptosis and energy supply of isolated rabbit heart muscle during perfusion with ropivacaine..

METHODSSixty New Zealand white male rabbits were randomized into 3 equal groups. In group I, the rabbits received a intreaperitioneal injection of distilled water 24 h before isolation of the heart with perfusion by Langendoff model; in group II, distilled water was injected intreaperitioneally, and 24 h later the heart was isolated and perfused with Langendoff model and ropivacaine; in group III, 3.6% ZnSO(4) was injected intreaperitioneally and the isolated heart was perfused with Langendoff model and ropivacaine. The myocardial metallothionein content, myocyte apoptosis, and myocardial ATP, ADP and AMP content were detected.

RESULTSThe myocardial metallothionein content was significantly higher in group III than in the other two groups; the percent of myocyte apoptosis was the highest in group II, and was significantly higher in group III than in group I. The myocardial content of ATP was the highest in group I, and was significantly higher in group III than in group II.

CONCLUSIONMetallothionein can significantly inhibit myocyte apoptosis and alleviate energy supply disorder induced by ropivacaine.

Amides ; pharmacology ; Animals ; Apoptosis ; drug effects ; Energy Metabolism ; drug effects ; In Vitro Techniques ; Male ; Metallothionein ; pharmacology ; Myocardium ; cytology ; metabolism ; Myocytes, Cardiac ; cytology ; metabolism ; Perfusion ; Rabbits

AIMTo examine the effects of pHi on [Ca2+]i, cell length and Ca2+ sensitivity of myofilaments in rat myocyte.

METHODSWe used microscopic spectral imaging approach to monitor simultaneously [Ca2+]i, pHi and cell length with fluorescent indicator indo-1 and SNARF-1 in isolated single rat myocyte.

RESULTSExposure of cell to 20 mmol/L Sodium Propionate induced an intracellular acidosis which increased slightly systolic and diastolic [Ca2+]i, decreased the cell shortening (CS) and Ca2+ sensitivity of myofilament (P < 0.01). Exposure of cell to 15 mmol/L NH4Cl induced an intracellular alkalosis which decreased systolic and diastolic [Ca2+]i, increased the cell shortening and Ca2+ sensitivity of myofilament (P < 0.01).

CONCLUSIONSIn the early time of acidosis, [Ca2+]i, as well as cell length increases respectively. While alkalosis, [Ca2+]i and cell length decreases respectively. The effect of acidosis and alkalosis on Ca2+ sensitivity presents non-linear relationship, i.e. the effect of acidosis on sensitivity, caused by pHi change, is less than that of alkalosis.

Animals ; Calcium ; metabolism ; Cell Size ; Hydrogen-Ion Concentration ; Male ; Myocardium ; cytology ; Myocytes, Cardiac ; metabolism ; Rats ; Rats, Wistar